Gov. Charlie Crist's decision to run as an independent in Florida has made news. But here's a November headline you probably won't see: "Crist elected to Senate."

Despite some promising polls, Crist is likely to find the road to victory is rough.

With credible Republican and Democratic candidates, he has to fight for a skimpy middle. A mix of disaffected Republicans, independents and moderate Democrats probably can't add up to electoral victory.

Recall how we got here. Crist was a popular moderate Republican governor. Republicans leaders were overjoyed when he said he would run for the open seat.

But Crist's announcement was the high point. As the economy deteriorated, his popularity has fallen like that of many other governors.

But more important, Crist was hit by the wave of conservative populism. This could down some Democrats in November, but is now making it hard for some establishment Republicans in primaries.

Crist's first misstep, or "misgesture"--hugging President Barack Obama when he visited Florida in February 2009 to promote his stimulus package.

Crist later backed away from his support. But the lasting image was a governor thanking the Democratic president for a program that is anathema to the tea party populism coursing through the veins of Republican primary voters.

Marco Rubio capitalized on this. The former Florida House speaker is younger, more conservative and more appealing to the tea partiers.

Rubio emerged as a clear favorite to beat Crist and then win the general election. Most polls showed Rubio beating Crist by 20 points.

So Crist's choice was clear: lose in the primary, or run as an independent. Polls give him a fighting chance. A recent Quinnipiac poll shows Crist winning 32 percent to Rubio's 30 percent, with Democrat Kendrick Meek at 24 percent.

The argument is that there is space between a conservative Republican and a liberal Democrat. Crist could be the candidate of the oft-forgotten middle.

But these polls overstate Crist's chances. They do not factor in the damage done by his leaving the Republican Party. His fund-raising has already taken a hit. In addition to donors, Crist could find that many Republican voters may also desert him--as he deserted the party.

Crist may be heartened by Sen. Joe Lieberman's 2006 win as an independent Democrat in Connecticut. Lieberman lost a Democratic primary and then beat a Democrat and Republican in the general. Crist may even have visions of the Crist-Lieberman independent caucus in the 112th Congress.

But the peculiar way that Lieberman won shows how unlikely it could be for Crist to follow the same path.

Lieberman lost a tough primary (52 percent to 48 percent) to the more liberal Ned Lamont. Then Lieberman switched to independent status.

I argued then that Lamont would win the lion's share of Democratic votes and that even a no-name Republican could win least 20 percent, leaving little room for Lieberman in the middle.

But I did not realize how the GOP would essentially throw its own candidate under the bus to support Lieberman. In the general, Lieberman received only one-third of Democratic votes, but the majority of Republican. The Republican candidate, Alan Schlesinger, received just 9.6 percent of the overall vote.

The problem for Crist is that Meek, the likely Democrat, is a reasonably strong candidate. In a two-way race with a Republican, he would probably take 40 percent, or possibly more. And as an African-American, Meek could win the black vote overwhelmingly. He may well lose, but he probably won't be marginalized as Schlesinger was in Connecticut.

So Crist, whose troubles began with a hug, will be the victim of another kind of squeeze.

Leaving the Republican Party will cost him the votes of moderate Republicans who might have supported him--but not after his decision to leave the party. Meanwhile, Crist is not likely to pick up enough Democratic votes.

What's left will be a disappointingly small share of the vote. In November, Crist is most likely to find himself a private citizen--not the next senator from Florida.

John C. Fortier is a research fellow at AEI.

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